Re: Re: How to create a trigger

Joseph Shraibman <jks@selectacast.net>

From: Joseph Shraibman <jks@selectacast.net>
To: "Thomas F. O'Connell" <tfo@monsterlabs.com>
Cc: pgsql-general@postgresql.org
Date: 2001-05-14T22:09:11Z
Lists: pgsql-general
See
http://www.brasileiro.net/postgres/cookbook/view-one-recipe.adp?recipe_id=10

"Thomas F. O'Connell" wrote:
> 
> > create trigger date_update before update on mytable
> >     for each statement execut procedure [procedure that inserts a date
> > for me in the update_date column]
> >
> > So what would I be doing for the portion in brackets?
> 
> at that point you need a function.
> 
> check out the CREATE FUNCTION syntax in the docs
> (http://www.postgresql.org/idocs/index.php?sql-createfunction.html).
> 
> for what you were talking about, it seems like something as simple as
> 
> create function trigger_before_update_mytable() returns opaque as '
> begin
>         new.update_date = now();
>         return new;
> end;
> ' as language 'plpgsql';
> 
> would work.
> 
> then your last line of the trigger statement would be:
> 
> for each statement execut procedure trigger_before_update_mytable();
> 
> good luck.
> 
> -tfo
> 
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-- 
Joseph Shraibman
jks@selectacast.net
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